Not all small turbo engines are more fuel-efficient says Consumer Reports

Consumer Reports isn't letting up on its testing of fuel efficiency claims for various vehicles. According to the publication, small turbocharged engines aren't delivering on the fuel efficiency claims by the manufacturers.

Small displacement turbocharged engines have become common in a variety of vehicles in place of larger displacement, naturally aspirated engines. The claim by the automotive manufacturers is that the small displacement turbocharged engines offer the same power as larger displacement engines and improved fuel efficiency.

Consumer Reports, however, states that in its real world testing many vehicles with turbocharged engines aren't as efficient as the manufacturers claim. The publication recently tested the 1.6-liter EcoBoost in a Ford Fusion and found that the turbocharged version has a slower 0-to-60 mph time than its competitors and achieved only 25 mpg in testing, making it among the worst for fuel efficiency in the recent crop of family sedans.

The publication also claims that the larger 2.0-liter turbocharged four-cylinder, which promises the power of the V-6 with the fuel economy of four-cylinder engine, fails to deliver on either front.

2013 Ford Fusion

Chevrolet is also under fire for the 1.4-liter turbo four-cylinder in the Cruze. Consumer Reports claims that real world performance wasn’t much better than the standard, naturally aspirated 1.8-liter engine and overall fuel economy was similar as well.

Ford and General Motors representatives offered similar statements explaining the discrepancy. "When you have an EcoBoost engine, you have the opportunity to have performance and fuel economy, but not at the same time,” said Ford Powertrain Communications Manager Richard Truett. “EcoBoost adds a dimension that you won't get by just making the engine smaller. We're telling the driver, it's up to you on how you want to drive."

"The Cruze turbocharged engine provides a much broader torque curve than a non-turbocharged engine, and that means better acceleration across the rpm range, making for a more fun-to-drive car,” said GM spokesman Tom Read. “However, if you have a heavy foot on a turbocharged engine, you're not necessarily going to see a lot of fuel economy benefits."

The EPA is going to investigate Ford after Consumer Reports and other owners have complained that fuel efficiency doesn't meet the automakers claims in the Fusion Hybrid and C-MAX.

quote: Were the blowhards at CR actually testing 0-60 speeds at the same time they were testing fuel efficiency...?

No. From Consumer Reports' page on their testing procedures:

quote: We perform our own fuel-economy tests, independent of the government's often-quoted EPA figures and the manufacturers' claims. Using a precise fuel-flow measuring device spliced into the fuel line, we run three separate circuits. One is on a public highway at a steady 65 mph. That circuit is run in both directions to counteract any wind effect. A second is a stop-and-go simulated city-driving test done at our track. The third is a 150-mile "one-day trip" using several drivers taking turns around a 30-mile loop of public roads that include a highway section, secondary roads, and rural byways. CR's overall fuel-economy numbers are derived from those three fuel consumption tests.

quote: Soooo how does one directly compare the results of one test to the results of another exactly?

Are you referring to comparing CR's results for different cars or comparing CR's results to EPA mpg figures?

For the former, CR's results should be relatively consistent as they test the same procedures and use more than one driver to generate each data point. So it should be valid to compare different cars using just CR's mpg figures.

Comparing CR's results with the EPA's is a little trickier, as the testing methodologies are different. However, it's worth noting that while there are many vehicles whose CR-attained mpg results match or exceed the EPA figures, every single turbo Ford in the test failed to meet its EPA rating on the CR cycle.

With a lack of information on what the exact cause is, I can only speculate that one or more of the following postulates are to blame:

1. CR's tests are worthless. I find this explanation the least likely as they should at least be useful for evaluating different vehicles being tested to CR's standard.

2. The EPA test procedure is flawed. There have been allegations that the EPA cycle does not replicate real world use and that manufacturers are gaming the system to achieve inflated numbers.

3. Ford is fudging their mpg figures. Whether this is from honest mistakes or a deliberate attempt to mislead the public is open to conjecture.

Personally, I consider a combination of 2. and 3. to be the most likely, but that is simply opinion for now. For the record, I average better than quoted mpg (by about 15-20%) in my wife's Fiesta (1.6L NA) and spot-on mpg in my Lancer Ralliart (2.0T). We were getting worse than quoted mpg (by about 10-20%) in our old 2008 G35x, so "YMMV" really does apply in all cases, it seems.

It does seem that way and thanks for the reply. Anecdotal but I have found Nissan's to be less fuel efficient than advertised in my driving also. My present car is spot on although I wonder how you have to drive and in what conditions to get their city rating (19 mpg). My worst is 23 and that was after a week of city only, spirited driving.

Unless the epa tests fords cars and concludes they lied, at this point, I am thinking number 2 is correct. There are numerous cars that are made to specifically ace the test. The fact that several plug in hybrids shut off their electric motors at 62mph (2 above what the epa test goes to from what I understand) points to gaming the system.

We will see now that the epa is investigating, and Ford will be hit with big fines and, more importantly, very bad press if they are found to be lying. If the epa comes up with basically the same numbers, then I think the test maybe needs to be updated, but that would probably take 10 years due to the way Washington works.